1. Field of the Invention
The present invention relates to a copier, fascimile apparatus, printer or similar electrophotographic image forming apparatus, a toner bottle to be packed with toner, or developer, for the apparatus, and a method of molding the toner bottle.
2. Description of the Background Art
An electrophotographic apparatus is conventional that forms a latent image on a photoconductive element, develops the latent image with charged toner, and then transfers the resulting toner image to a sheet. Usually, a toner container storing the toner is mounted to the apparatus. When the toner container runs out of the toner, it is replaced with a full toner container. Various kinds of toner containers have been proposed in the past, and each replenishes toner to the developing section of the apparatus in a particular manner.
As for a mechanism for discharging toner, toner containers are generally classified into two types, i.e., one that has agitating and discharging means thereinside and one that does not include such means, but is rotatable about its axis.
Japanese Patent Laid-Open Publication No. 7-20705, for example, discloses a rotation type of toner bottle to be mounted to the apparatus in a horizontal position. The toner bottle is rotated about its axis by drive means included in the apparatus, replenishing toner to the apparatus. This toner bottle has already been put on the market. The toner bottle has a mouth smaller in diameter than a body. Part of the toner bottle bulges out inward from the inner surface of a shoulder, which is formed at one end of the bottle where an opening is present, toward the edge of the opening. The bulging portion allows toner to be stably delivered from the toner bottle.
The problem with a toner bottle of the type taught in the above-mentioned document is that the drive means exerts a strong stress over the entire toner bottle when rotating the bottle. As a result, the toner leaks or flies about via the toner outlet of the mouth during operation due presumably to the stress.